Semiconductor package injection molding mold, injection molding device and semiconductor package injection molding method

Abstract

The present invention relates to the technical field of chip package, in particular to a semiconductor package injection molding mold, a semiconductor package injection molding device and a semiconductor package injection molding method. The semiconductor package injection molding mold includes a bottom mold and a top mold. The upper surface of the bottom mold is fitted with the lower surface of a substrate to form a semiconductor package structure; the top mold is matched with the bottom mold; the top mold has a cavity; the cavity is oriented toward the upper surface of the substrate and is used to accommodate a plastic package layer formed on the upper surface of the substrate; through holes that penetrate through the bottom mold are formed at positions corresponding to the substrate in the bottom mold; and the through holes are connected with an external pressure source.

What is claimed is: 
     
         1 . A semiconductor package injection molding device, comprising:
 a bottom mold;   a top mold;   a pressure source;   pneumatic electric control valves; and   a substrate,   wherein an upper surface of the bottom mold is fitted with a lower surface of the substrate; the top mold is matched with the bottom mold;   the top mold is provided with a cavity;   the cavity is oriented towards an upper surface of the substrate and is used to accommodate a plastic package layer formed on the upper surface of the substrate;   through holes that penetrate through the bottom mold are formed at positions corresponding to the substrate in the bottom mold;   the through holes are connected with the pressure source through the pneumatic electric control valves respectively;   the pressure source is configured to generate a positive pressure greater than an atmospheric pressure;   the positive pressure on the lower surface of the substrate generated by the pressure source is used to balance a pressure on the upper surface of the substrate during injection molding;   the lower surface of the substrate has bulges, and first through holes of the through holes are arranged at positions corresponding to the bulges;   a size of each of the first through holes is greater than a size of each of the bulges;   the pneumatic electric control valves are configured to control air pressures of the through holes such that air pressures corresponding to different through holes in the bottom mold are different, thereby forming different pressure distributions; and   the air pressures of the first through holes at the positions corresponding to the bulges of the lower surface of the substrate are greater than the air pressures of second through holes of the through holes at other positions corresponding to the lower surface of the substrate.   
     
     
         2 . The semiconductor package injection molding device according to  claim 1 , wherein the lower surface of the substrate further has grooves, and the second through holes are arranged at positions corresponding to the grooves. 
     
     
         3 . The semiconductor package injection molding device according to  claim 2 , wherein each of the grooves corresponds to at least one of the second through holes. 
     
     
         4 . The semiconductor package injection molding device according to  claim 2 , wherein pressure sensors are arranged in the first through holes and the second through holes respectively corresponding to the grooves and the bulges or on the lower surface of the substrate. 
     
     
         5 . The semiconductor package injection molding device according to  claim 1 , wherein air pressures corresponding to the same through hole at different times are adjusted through the pneumatic electric control valves. 
     
     
         6 . The semiconductor package injection molding device according to  claim 1 , wherein the pressure source is a pneumatic or hydraulic source. 
     
     
         7 . The semiconductor package injection molding device according to  claim 1 , wherein an injection molding technology is a transfer molding injection-molding technology. 
     
     
         8 . A semiconductor package injection molding method using the semiconductor package injection molding device of  claim 1 , comprising:
 superimposing, clamping and fixing the bottom mold, the substrate and the top mold, fitting the upper surface of the bottom mold with the lower surface of the substrate, orienting the cavity of the top mold towards the upper surface of the substrate and fitting the top mold with the upper surface of the substrate;   when the upper surface of the substrate forms the plastic package layer by a transfer molding technology, applying the positive pressure to the lower surface of the substrate by the pressure source through the through holes of the bottom mold, and balancing the pressure on the upper surface of the substrate during the injection molding by the positive pressure generated by the pressure source on the lower surface of the substrate,   wherein according to different substrates, the air pressures corresponding to the different through holes in the bottom mold are different, thereby forming the different pressure distributions.   
     
     
         9 . The semiconductor package injection molding method according to  claim 8 , wherein when the pressure on the upper surface of the substrate exceeds a preset value during transfer molding, the pressure source is opened and the pressure source is used to apply the positive pressure to the lower surface of the substrate through the through holes of the bottom mold. 
     
     
         10 . The semiconductor package injection molding method according to  claim 8 , wherein during transfer molding, the corresponding positive pressure to be applied to the lower surface of the substrate is calculated in real time by detecting the pressure generated on the upper surface of the substrate, and the pressure source is used to apply the corresponding positive pressure to the lower surface of the substrate through the through holes of the bottom mold. 
     
     
         11 . The semiconductor package injection molding method according to  claim 8 , wherein an injection molding technology is a transfer molding injection-molding technology.